Intelligent Beam Steering for Wireless Communication Using Programmable Metasurfaces

Abstract

Reconfigurable Intelligent Surfaces (RIS) are well established as a promising solution to the blockage problem in millimeter-wave (mm-wave) and terahertz (THz) communications, envisioned to serve demanding networking applications, such as 6G and vehicular. HyperSurfaces (HSF) is a revolutionary enabling technology for RIS, complementing Software Defined Metasurfaces (SDM) with an embedded network of controllers to enhance intelligence and autonomous operation in wireless networks. In this work, we consider feedback-based autonomous reconfiguration of the HSF controller states to establish a reliable communication channel between a transmitter and a receiver via programmable reflection on the HSF when Line-of-sight (LoS) between them is absent. The problem is to regulate the angle of reflection on the metasurface such that the power at the receiver is maximized. Extremum Seeking Control (ESC) is employed with the control signals generated mapped into appropriate metasurface coding signals which are communicated to the controllers via the embedded controller network (CN). This information dissemination process incurs delays which can compromise the stability of the feedback system and are

Smart Propagation Environments Empowered by Metasurfaces: A Self-Consistent Study

“…In a realistic system (see Fig. 1), we can implement reconfigurable metasurfaces [6], [7], [8], [9], [10] in some parts of the wall that represent the Dirichlet boundary condition (BC) with specific engineering, and the rest of the environment surrounding is modeled as a reflective wall. We have proposed proof of concept for one-dimensional media by engineering the surface impedance of the reflective metasurfaces [11], [12].…”

Free-Space Beam Steering with Twisted Bilayer Photonic Crystal Slabs

“…Beam steering, i.e. dynamically changing the direction of light beam in free space, is important for a number of applications including LiDAR and free-space communications. − Beam steering is commonly achieved with macroscopic optical setup, but there has been a long-standing interest in achieving this with more compact and power-efficient structures. − Thus, there have been extensively efforts in seeking to achieve beam steering with photonic chip structures. A few prominent approaches of photonic-chip-based beam steering include the use of optical phase array antennas, − slow-light waveguides, − and bilayer metasurfaces where each layer exhibits a phase gradient .…”

Toward Sub‐Terahertz: Space‐Time Coding Metasurface Transmitter for Wideband Wireless Communications

“…By manipulating the propagation path of EM waves, the metasurface can reconfigure the wireless environment to solve the signal coverage problems. [ 39 , 40 , 41 ] The time‐domain coding metasurface offers the ability to modulate the EM spectra in real time, enabling low‐cost wireless communication transmitters. [ 42 , 43 , 44 , 45 ] Definitely, the current attempts to apply for the time‐domain coding metasurfaces in communication systems have been focused primarily on low and medium frequency bands.…”